Mine has the 9 speed. No shortage of power or traction; was tired of spinning tires with my 5420's when pulling the 14' disc / 16' drag harrow combination. Pulls a Great Plains 1006NT like no tomorrow. Unless you are a row crop farmer, don't see where you would need more power. Best power & weight value with green paint. If I changed anything, I would swap the 9 speed for a 12 speed just to keep the rpm's where I want them.